• Machine Design Project for ME122F
  • Specific tasks for groups
    • Group I: Main frame and platform
    • Group II: First stage gear drive
    • Group III: The Reversing mechanism and screw
    • Group IV: Second stage gear drive
  • The Final Result

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Machine Design Project for ME122F?

Depending on which machine we decide to do (during week of May 3,5) we will divide into approx 4 groups with some assignments that we'll need to undertake to get the machine design and built.

MarkCutkosky May 5
OK, it is decided we are doing the giant 3-speed reversing ox-driven hoist. Therefore:

• Everybody needs to re-read pages 60-67 of Brunelleschi's Dome and take notes on all the factoids you can find (materials, dimensions, issues, problems...)
• Read over everything on the ThreeSpeedReversingOxDrivenHoist page and following the links to animations, models etc. The animations require decent Internet speed -- which means they only work if you try them first thing in the morning at the Stanford Florence campus.
• Try to figure out as many approximate dimensions as you can. Make sketchs and annotate them.
• As you wander around Florence, keep your eyes open for hardware stores (ferramenta).

A few more preliminary thoughts in MarksEmailOfMay9

Specific tasks for groups

Group I: Main frame and platform

(RobertTrevino? , RebeccaSawyer? , MackenzieCooper? )

Figure out main dimensions of a scale model. A likely good size is about 40cm long overall. That being the case, how high and wide should the model be? Use a large sheet of paper and ruler to draw side views, to-scale of the frame and note the approximate locations of the main shafts.

Go search in local ferramenta stores for wood of useful sizes. You want to note the dimensions so that you can size your model to involve minimum cutting. One ferramenta that has a selection of lumber is in Ferramenta Masini, via S. Gallo 60R (near the Questura see map below). (Check it out in http://www.tuttocitta.it and search "ferramenta" in the Pagine Gialle: http://www.paginegialle.it/index.html

Also be thinking about what size wood screws you'll be needing to join things.

Group II: First stage gear drive

(JackConte? , JeanWood? , MorganThrower? ) Consists of: 3 gears+ their shafts and supports for those shafts Given dimensions of roughly 40cm long (major dimension of the model) We need to figure out dimensions of the gears. How many teeth? What crown and root diameter?

• Check out the LanternGear page.
• Check out CutkoskyNotebook#Gears
• Read PreliminaryDesignMaterials

You can print out the gears on the ME21N? ThreeSpeedReversingOxDrivenHoist page and print them at various reductions (or use the copying machine and copy at various percentage scales) to get a sense of how teeth might mesh.

Group III: The Reversing mechanism and screw

(EutimiaMontoya? , MameiSun? , JaymievieveAng? , JessicaMok? ) We can manufacture a wooden screw mechanism of 3/4 inch diameter and mating threaded block. We need to figure out how to connect the screw, block, handle, and centering for the vertical shaft together so it actually works to accomplish the shifting.

The only way to figure this out is to draw a side view and cut-away cross section taken down the centerline of the screw mechanism.

Would be nice to also make the part that would connect to the oxen. Maybe even find some small oxen for scale?

Group IV: Second stage gear drive

(RaynaWiles? , RoelCordero? , MeghanKennedy? , AliceWarnecke? ) Includes: 2 gears + the shafts and supports for those shafts Given dimensions of roughly 40cm long (major dimension of the model) We need to figure out dimensions of the gears. How many teeth? What crown and root diameter?

• Check out the LanternGear page.
• Check out CutkoskyNotebook#Gears
• Read PreliminaryDesignMaterials

You can print out the gears on the ME21N? ThreeSpeedReversingOxDrivenHoist page and print them at various reductions (or use the copying machine and copy at various percentage scales) to get a sense of how teeth might mesh.

-- MarkCutkosky - 26 Apr 2005

• One ferramenta that has pieces of wood is Ferramenta Masini, via S. Gallo 60R

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The Final Result

June 7, 2005

The machine came together very well. The lasercut gears from Stanford fit perfectly. The vertical screw for adjustment also worked well. The frame also fit well although, in retrospect, it could have been a bit wider. Here are some pictures of the assembled machine:

details of primary and secondary gear sets meshing

detail of vertical adjustment screw